[JimMGZR]

Hi all!
I'm a new member here so please go easy on me!
I bought my MG ZR about 6 weeks ago and it has started overheating the last couple of days. If I drive around town it seems ok. But when I take it on to the major roads and hit 60-70 mph the temperature guage rises to the 3/4 mark instead of just below halfway.
I can't see any signs of leakage from the radiator or hoses although put a pot of Radweld Plus in this morning as it has been losing a small amount of coolant/water. This seemed to help earlier on today but just been out now and used a bit of speed and the temperature guage went high again, although this time the coolant level hasn't dropped.
If it helps- when the temperature guage goes high, as I come off the gas it seems to drop back to normal quite quickly.
I've not experienced an overheating problem like this before with any other make of car so hopefully someone here can give me a clue or has experienced this before!

Jim

 

[JimMGZR]

Worried!

In addition to the overheating issue I posted last night, I have checked the oil level and added a small amount. The coolant level appears ok this morning.
However, when starting it today the car is shuddering a bit and doesn't sound healthy.
There is fluid leaking from the joins in the exhaust system. I'm worried about driving it as not sure what the problem could be.
Can anyone help?

 

[Adam.pr]

Check for any leaks or signs of leaks on the head as it connects to the block. HG been done? Are you getting hot air from the heater?

 

[JimMGZR]

Hi Adam,

I can't see any signs of leakage. The HG hasn't been done that I know of although it was checked and found to be fine when I bought it 6 weeks ago. Just been out in it and it's running ok apart from the temperature guage. The heater is blowing hot.

 

[Adam.pr]

Alright, well check for any damage to the hoses coming from the radiator then check the radiator itself for any damage/corrosion/rust

 

[RikkiA335]

May be worth getting the cooling system pressure tested? Just as a precaution.

 

[JimMGZR]

I've checked all the hoses and the radiator, and no signs of any leakage. It had definitely been losing water but yesterday afternoon I put a pot of Radweld Plus in and the coolant level has only dropped a couple of ml since. It's definitely not the filler cap as no sign of leakage there either. Spoke to the Halfords Autocentre and they said it is definitely the Head Gasket(without looking at it!) I don't think it is though as there is no oil/water mix. This afternoon the car has run well, apart from the temperature guage rising and then dropping back to normal erratically on the dual carriageway but staying normal in town. It's certainly a strange one but I think it's something very minor. Where would I get the cooling system pressure tested please?

 

[Adam.pr]

It's definitely a strange one.. There is quite a few things it could be, though you wouldnt find out (if youre not mechanically minded) unless you went to a garage. Some sort of blockage or a dodgy water pump, temperature sensor.. You can get it pressure tested at any garage.

 

[JimMGZR]

I haven't got a great deal of spare cash this month so may just see how it goes for time being, and hope it doesn't get any worse. Definitely will keep a close eye on the coolant level. May give the system a flush over the weekend and see if that helps.

Thanks for the advice guys.

 

[Roverlike]

Hi Jim,

Can you change letter color as it is very hard to read your posts? It appear dark green and it can't be seen on dark background?

Anyway have two things on my mind. First one is airlock - did you made any coolant replacement recently?

Second is thermostat not functioning properly on higher revs. You are telling us that on town driving (I assume low revs, low speed) temp gauge is working fine?

How cooler fan behave? Does it kick in when it should? Did you tried to leave engine running while stationary (at home for example) and see if fan will kick in?

 

[rob dunster]

Hi Jim,

Can you change letter color as it is very hard to read your posts? It appear dark green and it can't be seen on dark background?

Anyway have two things on my mind. First one is airlock - did you made any coolant replacement recently?

Second is thermostat not functioning properly on higher revs. You are telling us that on town driving (I assume low revs, low speed) temp gauge is working fine?

How cooler fan behave? Does it kick in when it should? Did you tried to leave engine running while stationary (at home for example) and see if fan will kick in?

+1 for thermostat,as above,and +1 for colour change,my eyes won't be right for days now.

 

[JimMGZR]

Sorry about the green font, guys! Just chose it because it matched my ZR!
I haven't replaced the coolant as such, but topped it up where it has lost a bit this week. The temperature guage is normal until I hit about 60mph and then rises quickly to the 3/4 mark. As soon as I come off the gas and reduce speed it rapidly drops back to normal.
I haven't checked the fan while the car is idle. Will try that tonight. Thermostat had crossed my mind. Looking in the Haynes manual that looks quite a tricky job. I may give the cooling system a flush tomorrow. Do you reckon that would clear an air lock?

 

[Roverlike]

Sorry about the green font, guys! Just chose it because it matched my ZR!
I haven't replaced the coolant as such, but topped it up where it has lost a bit this week. The temperature guage is normal until I hit about 60mph and then rises quickly to the 3/4 mark. As soon as I come off the gas and reduce speed it rapidly drops back to normal.
I haven't checked the fan while the car is idle. Will try that tonight. Thermostat had crossed my mind. Looking in the Haynes manual that looks quite a tricky job. I may give the cooling system a flush tomorrow. Do you reckon that would clear an air lock?

Good flush to the system can be good start.

Yes you can remove airlock even with flush the system, but be sure that you do not create new airlock when you put new coolant in the system. Bleed the system good several times to be sure.

Make a check of the thermostat too.

 

[JimMGZR]

Update!

I still haven't managed to solve the issue but think I may be closer. I tried bleeding the cooling system just now and unscrewed the bleed screw until it came out... No Air, and no coolant either! The expansion tank still has coolant between the min and max positions so I reckon I've got some sort of a blockage.

Anyone any ideas?

Cheers

 

[southcoaststeve]

I had a similar issue with my 25, it turned out my thermostat had been fitted the wrong way round by the previous owner, I replaced this and also put a new radiator in and new expansion tank cap. solved my problem and car has been fine ever since.

I thought the Rad looked ok, but I whipped it out while doing the thermostat to give it a clean and it was absolutely shot to pieces. I got one from ebay for £30 (brand new) and it is working like a dream.

 

[JimMGZR]

Leak found!!

I drove to work this morning and again the temperature guage was ok and rose a bit. Just been out to the car and there is water/coolant dripping from what looks like the very left hand side of the engine. There don't appear to be any hoses directly above the leak so I reckon one of the gaskets somewhere has failed. Anybody got any ideas?

 

[Movies]

Check the Thermostat is working, that could be the cause of the previous problems.

Dripping from where you've mentioned could be the IMG, Waterpump or Thermostat housing.

 

[JimMGZR]

Thanks Movies.

I had a wet patch under the car about a week ago, but couldn't find a leak so put it down to parking over a puddle! But seen it dripping this time. It must be leaking intermittently as haven't really lost much coolant in the last week.
I don't know a great deal about cars so it's causing me a major headache!!

 

[Movies]

Was it dripping when the car was cold / hadn't been running for a while?

 

[JimMGZR]

Yes- got to work at 8. went outside about 11.45 and it was dripping. It stopped about 1pm.